fb: fix fb_pan_display range check
Fix the range check for panning. The current code fails to detect some invalid values (very high ones that can occur if an app tries to move further up/left than 0,0) as the check uses the unknown values for calculation so that an overflow can occur. To fix this it is sufficient to move the calculation to the right side to use only trusted values. Kai Jiang detected this problem and proposed an initial patch. Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de> Cc: Kai Jiang <b18973@freescale.com> Cc: Krzysztof Helt <krzysztof.h1@poczta.fm> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
parent
ff8147fe71
commit
99e9e7d62b
|
@ -871,8 +871,8 @@ fb_pan_display(struct fb_info *info, struct fb_var_screeninfo *var)
|
|||
err = -EINVAL;
|
||||
|
||||
if (err || !info->fbops->fb_pan_display ||
|
||||
var->yoffset + yres > info->var.yres_virtual ||
|
||||
var->xoffset + info->var.xres > info->var.xres_virtual)
|
||||
var->yoffset > info->var.yres_virtual - yres ||
|
||||
var->xoffset > info->var.xres_virtual - info->var.xres)
|
||||
return -EINVAL;
|
||||
|
||||
if ((err = info->fbops->fb_pan_display(var, info)))
|
||||
|
|
Loading…
Reference in New Issue